Slay operating mechanism for a loom

ABSTRACT

A slay operating mechanism for a loom comprises an operating rod adapted to be pivoted at one end to a slay; a bell crank lever, one arm of which is pivoted to the other end of the operating rod and the central portion of which is pivotally mounted on a shaft; a connecting rod pivoted at one of its ends to a second arm of the bell crank lever; an operating lever pivoted at one end to the other end of the connecting rod and at its other end to fixed structure; a beam pivoted intermediate its ends to the operating lever; two cams cooperating with the ends of the beam, each being mounted on a support shaft; a driving shaft for driving the cams; a Maltese cross for each cam and having at least four radial openings evenly distributed about the periphery thereof, each cam having at least one active face which cooperates, directly or indirectly, with one of the ends of the beam; an arm for each cam and rotatable with the driving shaft and axially movable relative thereto, each arm carrying, at its free end, a roller engageable into one of the openings and, a selection mechanism for selectively positioning the roller either in the plane of the Maltese cross or in a plane parallel to the plane of the Maltese cross; and a cam locking device for locking each cam in the selected position, the locking device being operated by the selection mechanism.

United States Patent [191 Hirsch et a1.

[ SLAY OPERATING MECHANISM FOR A LOOM [75] Inventors: Jean-JacquesHirsch, Neuilly;

Eugene Mayeur; Jacky Mayeur, both of Montreuil-Aux-Lions, all of France[73] Assignee: Societe en Commandite par actions dite: Adolphe et AndreCaen, Paris, France 22 Filed: Mar. 13,1972

[21 Appl. No.: 233,923

[30] Foreign Application Priority Data Aug. 14, 1973 PrimaryExaminer-Henry S. Jaudon Attorney-James E. Armstrong, Harold C. Wegnerct al.

[5 7] ABSTRACT A slay operating mechanism for a loom comprises anoperating rod adapted to be pivoted at one end to a slay; a bell cranklever, one arm of which is pivoted to the other end of the operating rodand the central portion of which is pivotally mounted on a shaft; aconnecting rod pivoted at one of its ends to a second arm of the bellcrank lever; an operating lever pivoted at one end to the other end ofthe connecting rod and at its other end to fixed structure; a beampivoted intermediate its ends to the operating lever; two camscooperating with the ends of the beam, each being mounted on a supportshaft; a driving shaft for driving the cams; a Maltese cross for eachcam and having at least four radial openings evenly distributed aboutthe periphery thereof, each cam having at least one active face whichcooperates, directly or indirectly, with one-of the ends of the beam; anarm for each cam and rotatable with the driving shaft and axiallymovable relative thereto, each arm carrying, at its free end, a rollerengageable into one of the openings and, a selection mechanism forselectively positioning the roller either in the plane of the Maltesecross or in a plane parallel to the plane of the Maltese cross; and acam locking device for locking each cam in the selected position, thelocking device being operated by the selection mechanism.

16 Claims, 10 Drawing Figures Patented Aug, 14, 1973 4 Sheets-Sheet 1Patented Aug. 14, 1973 4 Sheets-Sheet 4 SLAY OPERATING MECHANISM FOR ALOOM The present invention relates to slay operating mechanisms forlooms and, in particular, although not so restricted, to slay operatingmechanisms for ribbon looms.

Known slay operating mechanisms are of complicated construction and havea relatively slow operating speed.

The present invention seeks to provide a slay operating mechanism whereit is possible to control the positioning of a slay with a very highdegree of accuracy and at a high speed.

According to the present invention there is provided a slay operatingmechanism for a loom comprising: at least one operating rod adapted tobe pivoted at one end to a slay; at least one bell crank lever, one armof which is pivoted to the other end of the operating rod and thecentral portion of which is pivotally mounted on a shaft; a connectingrod pivoted at one of its ends to a second arm of the bell crank lever;an operating lever pivoted at one end to the other end of the connectingrod and at its other end to fixed structure; a beam pivoted intermediateits ends to the operating lever; two eccentric means cooperating withthe ends of the beam, each being mounted on a support shaft; at leastone driving shaft for acting upon at least one of the eccentric means,clutching means interposed between each eccentric means and a drivemeans and operable by an operating mechanism; each eccentric meanscomprising a cam and a Maltese cross having at least four radialopenings evenly distributed about the periphery thereof, each cam havingat least one active face which cooperates, directly or indirectly, withone of the ends of the beam; coupling means for each cam comprising atleast one arm rotatable with the driving shaft and axially movablerelative thereto, the or each arm carrying, at its free end, a rollerengageable into one of said openings and a selection mechanism forselectively positioning the roller either in the plane of the Maltesecross or in a plane parallel to the plane of the Maltese cross; and camlocking means for locking each cam in the selected position, the lockingmeans being arranged to be operated by the selection mechanism.

The selection mechanism for each cam may comprise a disc connected withthe said aim and having at least two segments of different diameters, astaged lateral ramp being provided on each face of the disc extendingprogressively from one end of the segment with the greater diametertowards a portion parallel with the plane of the disc, the selectionmeans including abutment means movable into the path of at least one ofthe two ramps to engage the ramp to effect axial displacement of thedisc and the arm, the abutment means cooperating with at least oneoperating member adapted to be operated by the operating mechanism.

Alternatively, the selection mechanism for each cam may comprise a dischaving at least one pair of segments of smaller'diameter and one pair ofsegments of greater diameter, a ramp on each side of the disc in anannular zone between the segments of smaller diameter and the segmentsof greater diameter, the segments of greater diameter beingsymmetrically and alternately disposed relative to the smaller diametersegments, and an abutment means arranged for movement in a planeperpendicular to that of the disc.

Preferably, each cam locking means comprises a plurality of arcuatesegments provided on each Maltese cross between adjacent openings, eachsegment having a radius of curvature the centre of which is located atsubstantially the axis of the driving shaft when the plane of symmetryof said each segment passes through the said axis, and a circularlocking disc the radius of which is the same as the radius of curvatureof the segments and which is at least axially movable on the saiddriving shaft and is axially fixed on the arm to cooperate with theselection mechanism, the arrangement being such that the plane ofsymmetry ofa segment coincides with the said axis of the driving shaftwhen the roller leaves or engages an opening in the Maltese cross.

The invention is illustrated, merely by way of example, in theaccompanying drawings, in which:

FIG. I is an elevational side view of the principal parts of a loomprovided with a slay operating mechanism according to the presentinvention;

FIG. 2 is a section, in plan, of the slay operating mechanism of FIG. 1;

FIG. 3 is a cross-section of the slay operating mechanism taken on theline IllIII of FIG. 2;

FIG. 4 is a cross-section of the slay operating mechanism taken on lineIVIV of FIG. 3;

FIG. 5 is a cross-section of part of the slay operating mechanism takenon the line V-V of FIG. 4;

FIG. 6 is a plan view, partly in section, showing part of the slayoperating mechanism;

FIG. 7 is a section on the line VIIVII of FIG. 6;

FIG. 8 is a plan view, partly in section, showing an altemativeconstruction of the part of the slay operating mechanism in FIG. 6; and

FIG. 9 is a section on the line IX--IX of FIG. 8.

FIG. 10 is a perspective view of the structure of selection disc 92-93.

In the following discussion references to front, rear, side,horizontal," vertical" etc. refer to the directions as seen in thedrawings.

Referring first to FIG. 1, there is shown a side view of a loom having aslay operating mechanism according to the present invention. The loomcomprises a frame 1 on which is mounted a motor 2 acting through a speedvariator 3 and a belt transmission 4 to drive a flywheel 5, therotational axis 6 of which is housed in the frame 1. A rear end 7a of adriving rod 7 is mounted eccentrically and radially adjustably on theflywheel 5. A front end 7b of the driving rod is pivoted to a square 8.The square 8 is supported by two suspension or support levers 9, 10. Thelower ends of the support levers 9, 10 are pivoted to the frame 1 atarticulation points l3, 14 respectively, and the upper ends of thesupport levers 9, 10 are pivoted to the square 8 at articulation pointsll, 12 respectively. The articulation points 11, 12 and 13, 14 are atthe same horizontal level. The four articulation points, together withthe support levers 9, 10, define a deformable parallelogram. On thefront face of the square 8 a beam 15 is pivoted at 26, 27, the beamextending along the length of the front face of the loom and is pivotedon the other side face (not shown) of the loom and, if need be, also atthe centre of the loom, on another square identical to the square 8.Moreover, on this other side face, and also possibly at the centre ofthe loom, there is provided a further driving rod and a further flywheeldriven by the speed variator 3.

The beam supports a slay 16 which extends along the entire width of thefront face of the loom and is mounted for vertical movement in guides1150 on the beam 15. The slay 16 is provided with one or more sets 17,18 of groups of superimposed shuttles 17, 18. For greater simplicity, aslay operating mechanism for the shuttles 17, 18 has only beenrepresented diagrammatically at 19 in FIG. 1. A transmission 20 causesmovement of the slay 16 in response to the slay operating mechanism. Theslay operating mechanism will be described in greater detailhereinafter.

Two sheds 21, 22, healds 23, a stop motion device 24 and a loom beam 25are indicated diagrammatically in FIG. 1.

The transmission 20 comprises an operating rod one end of which ispivotally connected to the lower end of the slay 16 and the other end ofwhich is pivotally connected to one arm 31a of a bell crank lever 31.The lever 31 has a shaft part 32 which extends over the entire width ofthe loom and has a second arm 31b. It will be appreciated that aplurality of arms, similar to the arm 21a, may be provided on the shaftpart 32, these arms being distributed therealong and each beingconnected to the slay 16 by a respective rod similar to the rod 30. Inthis case, the arms 21a and the rods 30 will be parallel to one another.The second arm 31b of the bell crank lever 31 is arranged vertically andis pivoted at its free end to a connecting rod 33 which is substantiallyhorizontal. The rod 33 extends through an opening 35 in the front faceof a casing 34 of the slay operating mechanism 19 (see FIG. 2). Thus theslay operating mechanism will cause vertical reciprocating movement ofthe slay 16.

As seen in FIG. 1, the slay comprises two sets 17, 18 of threevertically disposed shuttles. The number of shuttles in each set is, inthis embodiment, three so that the slay 16 can take up three differentpositions: that is to say, there are three positions of the slay 16where there is a shuttle at the level of each of the sheds 21, 22. Theslay 16 is in its centre position when the centre shuttle of each set isat the level of the sheds 21, 22.

It will be appreciated that when the rod 33 causes the bell crank lever31 to pivot in a clockwise direction, the slay 16 is brought into itslowermost position in which the upper shuttle of each set is located atthe level of the sheds, and when the bell crank lever 31 is pivoted inan anticlockwise direction, the slay is brought into its uppermostposition in which the lower shuttle of each set is located at the levelof the sheds 21, 22.

The invention is not limited to the sets comprising three verticallyarranged shuttles, it also applies to the case where the sets comprisetwo vertically arranged shuttles or more than three vertically arrangedshuttles.

Referring now to FIGS. 2 and 3, the rear end of the rod 33 is pivoted tothe upper end of an operating lever 36, the lower end of which ispivotally mounted on a shaft 36 located in bearing 38 secured to thecasing 34. For reasons of symmetry, the operating lever 36 has twolateral cheeks 36a, 36b parallel to one another and interconnected attheir ends by shafts 37, 39. The lever 36 pivots about the shaft 37after rod 33 pivots about the shaft 39. A beam 40 is pivotally mountedon a shaft 41 connected to the centre of the lever 36. The beam 40 has,on either side of the shaft 41, two arms of equal length, the totallength of the beam 40 being less than the distance between the twoshafts 37, 39. The beam is arranged between the two lateral cheeks 36a,36b of 4 the lever 36 and also comprises two cheeks 40a, 40b.

Two operating earns 42, 43 are provided and one cam cooperates with eachend of the beam 40. Each cam 42, 43 is free to rotate about, but isaxially fixed on, a supporting shaft 44, 45 respectively. Thesesupporting shafts 44, 45 are parallel and vertically arranged one abovethe other. The ends of the shafts are mounted in suitable bearings 46,47 respectively on the casing 34.

The earns 42, 43 may be connected directly on the ends of the beam 40.In this case, the ends of the beam are urged against an active surfaceon each of the earns 42, 43 by means of springs (see FIG. 6 and 7).

In the case where the slay 16 is capable of taking one of threedifferent positions, that is to say, uppermost, centre and lowermostpositions, the two cams each have an active surface consisting of twoactive faces 42a and 42b, 43a and 43b symmetrically disposed to eachother relative to the respective supporting shaft 44, 45. The two activefaces of each cam may, for example be a disc freely mounted on the axisof the respective supporting shaft, the two active faces havingdifferent radii of curvature. The centre of-curvature of the two activefaces coincides with the axis of the respective supporting shaft and areinterconnected by flat faces. This case is illustrated on FIG. 6 and 7.Again, the ends of the beam 40 are constantly urged by springs 62against the corresponding cams 42, 43. When the two ends of the beam 40rest against the active faces which have the smaller radius ofcurvature, i.e. the active faces which are nearer the supporting shafts44, 45, the lever 36 is pivoted and, according to the arrangement shownin FIG. 1, the slay l6 occupies its uppermost position. On the otherhand, when the ends of the beam 40 engage the active faces which have agreater radius of curvature, i.e., are the furthest from the supportingshafts 44, 45, the lever 36 pivots about the shaft 37 so that the slay16 is in its lowermost position. The slay 16 is in its centre positionwhen the active face with the smaller radius of curvature of one of thecams is in contact with one of the ends of the beam 40 while the activeface with the greater radius of curvature of the upper cam is in contactwith the other end of the beam 40.

The active surfaces of the cams may be constituted by grooves 48, 49 ofsuitable section made in a lateral face of a disc-like cam. Spigots 50,51 are engaged in the grooves 48, 49 respectively. Each of the spigots50,

. 51 is mounted on the end of a connecting rod 52, 53.

The other ends of the connecting rods are pivotally mounted on oppositeends of the beam 40. Preferably, the two cheeks 40a, 40b of the beam areconnected at their ends by means of respective shafts 54, 55 on whichthe connecting rods 52, 53 are pivotally mounted.

The earns 42, 43 are freely mounted on their respective supportingshafts 44, 45, for example by means of suitable ball bearings 56, 57respectively. Alternatively, they may be splined onto their respectivesupporting shafts which are then mounted for rotation in the bearings46, 47.

Each of the grooves 48, 49, represented in dotted lines in FIG. 3, hasfour active faces arranged around the respective supporting shaft atintervals. Naturally when each cam has only two active faces, the latterare angularly spaced apart by This spacing of the active faces isemployed in the case where the active faces form the profile of the camas well as in the case when the active faces are formed in a groove. Theradial extent of the active faces on each of the cams may be relativelysmall. Nevertheless, the extent must be large enough to constitute acorrect supporting area, either directly for the corresponding end ofthe beam 40 or for a respective spigot 50, 51 on the connecting rods 52,53. The portions of the active surface between the two active faces ofeach cam may exhibit any profile preferably continuous and progressive,but in no event should these portions be at a distance from therespective supporting axis which is less or greater than that of theactive faces.

The use of a cam having a groove therein, where the active surface ofsaid groove is parallel with the respective supporting shaft, isparticularly advantageous because it makes it possible to provide eachof the cams 42, 43 with two pairs of active faces 42a, 43a and 42b, 43brespectively. The active faces 42a, 43a of the respective cams arediametrically opposed to each other and alternate with the respectiveactive faces 42b, 43b. In this case the active faces 42a, 43a have agreater radius of curvature and so are disposed at a greater distancefrom the respective supporting shaft thanthe active faces 42b, 43b whichhave a smaller radius of curvature and thus are closer to the respectivesupporting shaft. The active surfaces 42a, 43a are convex and the actingsurfaces 42b, 43b are concave.

In view of the fact that the active faces are spaced apart by 90 aroundeach cam a quarter of a complete revolution of the cam is sufficient tochange the active face cooperating with one end of the beam 40. Thus,the rate of change of position of the slay 16 is considerably increased.

The tops or recesses of the active faces 42a, 42b or 43a, 43b have,preferably, a more pronounced curvature so as to prevent an undesirablelateral shift of the respective spigot 50, 51 in a horizontal planepassing through the supporting shaft 44, 45. The shafts 54, 55 of thebeam 40 are also located in this horizontal plane in each of itspositions corresponding to the three positions of the slay 16. Only whenone end of the beam 40, for example the end carrying the shaft 54,passes from one position to another while the other end, for example theend carrying the shaft 55, retains its initial position, does the shaft54 depart slightly and temporarily from this horizontal plane. Thisdeparture is, however, very small and does not have any appreciableinfluence upon the lever 36 because the beam 40 is relatively long.

instead of a groove in each cam, it is possible to have an internalshoulder of suitable profile on each cam behind which shoulder thespigot 50, 51 respectively is engaged. Indeed, as the shaft 41 of thelever 36 is constantly urged by the weight of the slay 16, the radiallyinner face of the groove does not engage the respective spigot and sodoes not play any essential part. Thus when a shoulder is used in placeof the groove, it is unnecessary to provide a shoulder corresponding tothe radially inner face of the groove.

When the four active faces form the profile of each cam it isadvantageous either to guide the respective spigot 50, 51 in thehorizontal plane or to make a rigid connection between the respectiveconnecting rod 52, 53 and the corresponding end of the beam 40 and tourge the spigot 50, 51 towards the active faces by means of a spring. inthe case of this rigid connection between the connecting rods 52, 53 andthe beam 40, the active faces 42a, 42b and 43a, 43b will require anadequate area to take into account the angular displacement of the endsof the connecting rods 52, 53.

The two alternative constructions of the cams discussed above are shownin FIGS. 6 to 9. For each construction only one of the cams will bedescribed but it will be appreciated that the other cam is of similar oridentical construction.

As may be seen in FIGS. 6 and 7 the cam 42 is mounted by means of thebearings 56 on the supporting shaft 44 and has four active faces 42a,42b on its profile. The active faces are equi-angularly spaced apart by90 and are alternately disposed. The active faces 42a are disposed at agreater distance from the supporting shaft 44 than the active faces 42b.It will be observed that opposite the spigot 50 the connecting rod 52has a guide finger 59 slidably mounted in a horizontal slide 60, 61integral with the casing 34 and forming with the spigot an articulationof the connecting rod 52. This guiding of the spigot 50 ensures thatonly the position of the cam 42 in relation to the spigot 50 determinesthe position of the beam 40. A return spring 62 is fixed between theguiding finger 59 and the shaft 44 to urge the spigot 50 towards the cam42.

in FIGS. 8 and 9 there is shown a construction for the cam 43 which ismounted for free rotation on its supporting shaft 45 through thebearings 57. As in the previous embodiment, the cam 43 is prevented fromaxial movement by means of safety washers 64 embedded in the hub of aMaltese cross 66 on which the cam 43 is keyed and which will bedescribed later. Opposite the spigot 51, the connecting rod 53 has aguiding finger 59 which is coaxial with the said spigot 51 and which isguided along a horizontal plane passing through the axis of thesupporting shaft 45, through suitable slides 60, 61 integral with thecasing 34. The spigot is urged to bear upon an internal shoulder 58 ofthe cam 43 by the weight of the slay 16, which always exerts a forceupon the ends of the beam 40. This internal shoulder 58 has four activefaces 43a, 43b equi-angularly spaced apart by 90 and alternatelydisposed relative to one another.

As will be seen from FIGS. 2, 3 and 6 to 9 each cam 42, 43 is fixed to aMaltese cross 66. Each Maltese cross 66 is free to rotate about, but isaxially fixed on a respective supporting shaft 44, 45. Each Maltesecross 66 has at least four radial openings 67, 68, 69, which are openlaterally on the side opposite to the cam 42, 43 respectively. Theseradial openings 67 to 70 are equi-angularly spaced apart and, in theembodiment illustrated, are spaced apart by 90". At least one roller 71,carried by an arm 73, is arranged on a principal drive shaft through ahub 77. At least one roller 72 is carried by an arm 74 and is arrangedon an auxiliary drive shaft 76 through a hub 78. The hubs 77, 78 of thearms 73, 74 respectively are axially movable on the respective shafts75, 76 each of which is provided with coaxial grooves or splines 79evenly distributed over the periphery along a portion of the lengththereof. The hubs 77, 78 have corresponding grooves or splines 80. Theshafts 75, 76 are arranged in the same horizontal planes as thesupporting shafts 44, 45 respectively. The location of the rollers 71,72 is such that for a first position of the arms 73, 74 they extendradially into openings in the Maltese crosses 66 and in a secondposition they abut the periphery of the Maltese crosses between adjacentopenings. As illustrated in FIG. 3 each arm 73, 74 has two rollers 71,72 respectively diametrically opposed to each other.

At the openings 67 to 70 the circumference of each Maltose cross 66 isformed by arcuate segments the centre of curvature of which is locatedat the axis of the respective supporting shaft. Between each pair ofopenings there is provided a circumferential locking segment 81. Eachsegment 81 is arcuate, the centre of curvature of which is the principaldrive shaft 75 or the auxiliary drive shaft 76. When a segment 81 isengaged with a correspondingly shaped portion of the respective arm, itis symmetrically disposed about the horizontal plane passing througheither of the shafts 44, 75 or the shafts 45, 76.

The length of the arms 73, 74 and the radial depth of the openings 67 to70, account being taken of the distance between the shafts 75, 76 andthe shafts 44, 45, are selected in such a way that the engagement of theroliers 71, 72 in an opening causes rotation of the Maltese cross by aquarter of a revolution. It is important that the tops or recesses ofthe active faces 42a, 42b, 43a, 43b of each cam 42, 43 should coincidewith the plane of symmetry between two adjacent openings. Thus, in FIG.3, the active surface 420 of each cam coincides with the plane ofsymmetry between the two adjacent openings 69, 70, said plane ofsymmetry being that of the segment 81.

With each of the segments 81 of each Maltese cross, there is acooperating circular locking disc 82, 83 which is mounted on the hub 77,78 respectively in such a way as to be axially movable relative to theshafts 75, 76 and to be axially fixed relative to the arm 73, 74. Eachlocking disc 82, 83 and the respective arm 73, 74 are arranged inrelation to each other in such a way that either can operate alternatelywith the corresponding Maltese cross 66. Each locking disc has acircular profile and a diameter such that it can be engaged laterally ina segment 81 of a Maltese cross 66 when the latter occupies a positionin which the horizontal plane passing through the principal drive shaftor the auxiliary drive shaft constitutes the plane of symmetry of thesegment. This is always the case when a roller 71, 72 has just left oneof the openings 67 to 70 of each Maltese cross 66. At this moment, anactive face 42a, 42b and 43a, 43b of each cam 44, 45 respectivelyoccupies its operating position and the locking disc engages a segment81, so that the latter is immobile during the subsequent rotation of theshaft 75, 76 respectively. Thus, the stresses acting upon the slay 16and consequently upon the lever 36 and the beam 40, cannot influence therotation of the shafts 75, 76.

It is; moreover, advantageous to mount each locking disc 82, 83 on thecorresponding hub 77, 78 through a bearing 84, 85 and to prevent anyaxial displacement of the locking disc in relation to its hub by meansof a safety washer 86, 87 respectively.

When a locking disc 82, 83 is engaged with its respective Maltese cross66, the roller moves along a plane parallel to that of the Maltese cross66 and cannot be engaged in one of the openings 67 to 70. The principaldrive shaft 75 is driven by the speed variator 3. As shown in FIG. 4,the auxiliary shaft 76 is driven from the shaft 75 by means of a toothedreversing wheel 88 which is freely mounted on an intermediate shaft 89and engages, on the one hand, with a toothed wheel 90 keyed to the shaft75 and, on the other hand, to a toothed wheel 91 keyed to the shaft 76.Of course, the wheel 88 and the wheels 90, 91 may be replaced by anyother means such as a chain transmission, a notched belt transmission,etc.

Each locking disc 82, 83 has a respective selection mechanism forcausing its axial displacement and simultaneous displacement of therespective arms 73, 74 along the corresponding shaft 75, 76. Theselection mechanism is shown in FIG. 2, 3 and 5 and comprises for eachMaltese cross 66 a selection disc 92, 93 connected for rotational andaxial displacement with the corresponding arm 73, 74. Each selectiondisc 92, 93 comprises at least two parts or segments 94, 95 of differentdiameters. The segment 94 has the greater diameter and comprises, whenthere is only one segment of this type, on each side a staged lateralramp starting (seen in the direction of rotation of the disc 92, 93indicated by the arrow f) progressively along a slope 98 towards aportion 99 of the ramp, this portion being parallel to the face of thedisc 92, 93. The segment 95 of smaller diameter is radially retracted inrelation to the ramp and serves for the passage ofa selection abutment100, 101. The abutment may be disposed in the path of the slope 98 andimmobilised in that position so that, when the slope comes into contactwith this abutment, the selection disc 92, 93 moves to the right or tothe left taking with it the respective roller 71, 72 and the lockingdisc 82, 83 until the portion 99 of the ramp bears against the abutment.It should be noted that the peripheral length of the portion 99 of theramp is of little importance as it does not serve to keep the respectiveroller 71, 72 and the locking disc 82, 83 in a selected position.Indeed, no axial stress, with the exception of that originating from theabutment 100, 101 can act on the roller 71, 72, the arm 73, 74 and thelocking disc 82, 83. The angular position of the slope 98 in relation tothe arm 73, 74 is selected in such a way that immediately after a roller71, 72 comes out of an opening 67 to this slope 98 can cooperate withthe abutment 100, 101.

As seen in FIGS. 2 to 5 and 10 each selection disc 92, 93 comprises twopairs of diametrically opposed ramps on opposite sides of the saidselection disc. Each pair of ramps is separated from the other by anangular recess the bottom of which delimits the segment of smallerdiameter. This arrangement enables the axial displacement of the roller71, 72 and of the locking disc 82, 83 at each half revolution of thedriving shaft 75, 76 respectively.

The displacement of the abutment 100, 101 is obtained with the aid of aset of levers 100, 104 pivoted, on the one hand, about a pivot 105, 106respectively fixed to the casing 34 and, on the other hand, about aelectromagnet 107, 108 respectively receiving its operating impulsesfrom a Jacquard mechanism or the like.

According to an alternative form of selection mechanism, two abutmentsare placed on either side of each selection disc in such a way that eachis capable of being interposed in the path of one of the two ramps onthe selection disc. Each abutment, for example, constituted by a rollermounted so as to move around the axis perpendicular to that of theselection disc, is mounted on the end of a rod axially movable in aplane parallel with that of the selection disc, each rod being rigidlyguided in its axial displacement and carrying, between its two ends, atoothed rack engaging with a toothed transmission wheel. The toothedracks of the two rods are in engagement with the toothed transmissionwheel on either side of the rotational axis of the latter and in such away that when one of the abutments is interposed in the path of one ofthe ramps the other abutment is removed from the path of the other ramp.The transmission wheel is controlled by the operative part of theelectromagnet of a Jacquard mechanism through another toothed rackconnected with the operative part of the electromagnet.

We claim: 1

l. A slay operating mechanism for a loom comprising: at least oneoperating rod adapted to be pivoted at one end to a slay; a bell cranklever; two arms on the bell crank lever, one arm being pivoted to theother end of the operating rod; a shaft on which the central portion ofthe bell crank lever is pivotally mounted; a connecting rod pivoted atone of its ends to the second arm of the bell crank lever; an operatinglever pivoted at one end to the other end of the connecting rod; fixedstructure on which the other end of the operating lever is pivotallymounted; a beam pivoted intermediate its ends to the operating lever;two eccentric means cooperating with the ends of the beam; a supportshaft for each eccentric means; at least one driving shaft for actingupon at least one of the eccentric means; drive means; clutching meansinterposed between each eccentric means and the drive means and operableby an operating mechanism; each eccentric means comprising a cam and aMaltese cross; at least four radial openings defined by each Maltesecross and evenly distributed about the periphery thereof; at least oneactive face on each cam cooperating, directly or indirectly, with one ofthe ends of the beam; at least one arm rotatable with the driving shaftand axially movable relative thereto and comprising coupling means; aroller at the free end of the at least one arm, the roller beingengageable into one of said openings; a selection mechanism forselectively positioning the roller either in the plane of the Maltesecross or in a plane parallel to the plane of the Maltese cross; and camlocking means for locking each cam in the selected position, the lockingmeans being arranged to be operated by the selection mechanism.

2. A slay operating mechanism as claimed in claim 1 in which theselection mechanism for each cam comprises a disc connected with thesaid arm having at least two segments of different diameters, a stagedlateral ramp being provided on each face of the disc extendingprogressively from one end of the segment with the greater diametertowards a portion parallel with the plane of the disc, the selectionmeans including abutment means movable into the path of at least one ofthe two ramps to engage the ramp to effect axial displacement of thedisc and the arm, the abutment means cooperating with at least oneoperating member adapted to be operated by the operating mechanism.

3. A slay operating mechanism as claimed in claim 1 in which theselection mechanism for each cam comprises a disc having at least onepair of segments of smaller diameter and one pair of segments of greaterdiameter, a ramp on each side of the disc in an annular zone between thesegments of smaller diameter and the segments of greater diameter, thesegments of greater diameter being symmetrically and alternatelydisposed relative to the smaller diameter segments, and an abutmentmeans arranged for movement in a plane perpendicular to that of thedisc.

4. A slay operating mechanism as claimed in claim 2 in which theabutment means is mounted on a curved end of a selection lever pivotedbetween its ends on a fixed shaft, the other end of the selection leverbeing arranged to be operated by the operating mechanism.

5. A slay operating mechanism as claimed in claim 3 in which theabutment means is mounted on a curved end of a selection lever pivotedbetween its ends on a fixed shaft, the other end of the selection lever,being arranged to be operated by the operating mechanism.

6. A slay operating mechanism as claimed in claim 2 in which theabutment means comprises two abutments each of which is movable into thepath of one of the two ramps and is mounted on the end of a rod axiallymovable in a plane parallel to that of the disc, each of the rodscarrying a toothed rack engaging with a toothed transmission wheel insuch a way that when one of the abutments is interposed in the path ofone ramp the other abutment is out of the path of the other ramp, thetoothed transmission wheel being controllable by the operatingmechanism.

7. A slay operating mechanism as claimed in claim 3 in which theabutment means comprises two abutments each of which is movable into thepath of one of the two ramps and is mounted on the end of a rod axiallymovable in a plane parallel to that of the disc, each of the rodscarrying a toothed rack engaging with a toothed transmission wheel insuch a way that when one of the abutments is interposed in the path ofone ramp the other abutment is out of the path of the other ramp, thetoothed transmission wheel being controllable by the operatingmechanism.

8. A slay operating mechanism as claimed in claim 1 in which each camlocking means comprises a plurality of arcuate segments provided on eachMaltese cross between adjacent openings, each segment having a radius ofcurvature the centre of which is located at substantially the axis ofthe driving shaft when the plane of symmetry of said each segment-passesthrough the said axis, and a circular locking disc the radius of whichis the same as the radius of curvature of the segments and which is atleast axially movable on the said driving shaft and is axially fixed onthe arm to cooperate with the selection mechanism, the arrangement beingsuch that the plane of symmetry of a segment coincides with the saidaxis of the driving shaft when the roller leaves or engages an openingin the Maltese cross.

9. A slay operating mechanism as claimed in claim 1 in which at leastone of the cams has an active surface consisting of at least one pair ofactive faces symmetrically disposed relative to each other about therespective support shaft, one of the two active faces of the pair ofactive faces being nearer the support shaft than the other.

10. A slay operating mechanism as claimed in claim 1 in which each ofthe two cams has an active surface consisting of two active faces one ofwhich is located nearer the respective support shaft than the other,corresponding active faces on the two cams having the same profiles.

11. A slay operating mechanism as claimed in claim 9 in which the activeface or faces of each cam are constituted by a closed groove in a discmounted on the respective support shaft.

12. A slay operating mechanism as claimed in claim 9 in which the activeface or faces of each cam are provided on a shoulder of a disc mountedon the respective support shaft, a spigot on one end of a connecting rodbeing provided to cooperate with said shoulder, the other end of saidconnecting rod being pivoted to one end of the beam.

13. A slay operating mechanism as claimed in claim 9 in which the activeface or faces of each cam are provided on the profile of a disc mountedon the respective support shaft.

14. A slay operating mechanism as claimed in claim 13 in which each camhas a connecting rod with a spigot at one end, the spigot being urgedinto contact with the profile, the other end of the connecting rod beingconnected to one end of the beam.

15. A slay operating mechanism as claimed in claim 9 in which each camhas at least two pairs of active faces, one of the pairs of active facesbeing nearer the respective support shaft than the other pair, activefaces of each of the pairs being alternately and equiangularly spacedapart.

16. A slay operating mechanism as claimed in claim 12 in which eachconnecting rod has, on the side opposite to the spigot, a guide fingerwhich is coaxial with the spigot, the guide finger being engaged in aslide, the

, plane of which includes the respective support shaft.

1. A slay operating mechanism for a loom comprising: at least oneoperating rod adapted to be pivoted at one end to a slay; a bell cranklever; two arms on the bell crank lever, one arm being pivoted to theother end of the operating rod; a shaft on which the central portion ofthe bell crank lever is pivotally mounted; a connecting rod pivoted atone of its ends to the second arm of the bell crank lever; an operatinglever pivoted at one end to the other end of the connecting rod; fixedstructure on which the other end of the operating lever is pivotallymounted; a beam pivoted intermediate its ends to the operating lever;two eccentric means cooperating with the ends of the beam; a supportshaft for each eccentric means; at least one driving shaft for actingupon at least one of the eccentric means; drive means; clutching meansinterposed between each eccentric means and the drive means and operableby an operating mechanism; each eccentric means comprising a cam and aMaltese cross; at least four radial openings defined by each Maltesecross and evenly distributed about the periphery thereof; at least oneactive fAce on each cam cooperating, directly or indirectly, with one ofthe ends of the beam; at least one arm rotatable with the driving shaftand axially movable relative thereto and comprising coupling means; aroller at the free end of the at least one arm, the roller beingengageable into one of said openings; a selection mechanism forselectively positioning the roller either in the plane of the Maltesecross or in a plane parallel to the plane of the Maltese cross; and camlocking means for locking each cam in the selected position, the lockingmeans being arranged to be operated by the selection mechanism.
 2. Aslay operating mechanism as claimed in claim 1 in which the selectionmechanism for each cam comprises a disc connected with the said armhaving at least two segments of different diameters, a staged lateralramp being provided on each face of the disc extending progressivelyfrom one end of the segment with the greater diameter towards a portionparallel with the plane of the disc, the selection means includingabutment means movable into the path of at least one of the two ramps toengage the ramp to effect axial displacement of the disc and the arm,the abutment means cooperating with at least one operating memberadapted to be operated by the operating mechanism.
 3. A slay operatingmechanism as claimed in claim 1 in which the selection mechanism foreach cam comprises a disc having at least one pair of segments ofsmaller diameter and one pair of segments of greater diameter, a ramp oneach side of the disc in an annular zone between the segments of smallerdiameter and the segments of greater diameter, the segments of greaterdiameter being symmetrically and alternately disposed relative to thesmaller diameter segments, and an abutment means arranged for movementin a plane perpendicular to that of the disc.
 4. A slay operatingmechanism as claimed in claim 2 in which the abutment means is mountedon a curved end of a selection lever pivoted between its ends on a fixedshaft, the other end of the selection lever being arranged to beoperated by the operating mechanism.
 5. A slay operating mechanism asclaimed in claim 3 in which the abutment means is mounted on a curvedend of a selection lever pivoted between its ends on a fixed shaft, theother end of the selection lever, being arranged to be operated by theoperating mechanism.
 6. A slay operating mechanism as claimed in claim 2in which the abutment means comprises two abutments each of which ismovable into the path of one of the two ramps and is mounted on the endof a rod axially movable in a plane parallel to that of the disc, eachof the rods carrying a toothed rack engaging with a toothed transmissionwheel in such a way that when one of the abutments is interposed in thepath of one ramp the other abutment is out of the path of the otherramp, the toothed transmission wheel being controllable by the operatingmechanism.
 7. A slay operating mechanism as claimed in claim 3 in whichthe abutment means comprises two abutments each of which is movable intothe path of one of the two ramps and is mounted on the end of a rodaxially movable in a plane parallel to that of the disc, each of therods carrying a toothed rack engaging with a toothed transmission wheelin such a way that when one of the abutments is interposed in the pathof one ramp the other abutment is out of the path of the other ramp, thetoothed transmission wheel being controllable by the operatingmechanism.
 8. A slay operating mechanism as claimed in claim 1 in whicheach cam locking means comprises a plurality of arcuate segmentsprovided on each Maltese cross between adjacent openings, each segmenthaving a radius of curvature the centre of which is located atsubstantially the axis of the driving shaft when the plane of symmetryof said each segment passes through the said axis, and a circularlocking disc the radius of which is the same as the radius of curvatureof the segments and which is at least axially movaBle on the saiddriving shaft and is axially fixed on the arm to cooperate with theselection mechanism, the arrangement being such that the plane ofsymmetry of a segment coincides with the said axis of the driving shaftwhen the roller leaves or engages an opening in the Maltese cross.
 9. Aslay operating mechanism as claimed in claim 1 in which at least one ofthe cams has an active surface consisting of at least one pair of activefaces symmetrically disposed relative to each other about the respectivesupport shaft, one of the two active faces of the pair of active facesbeing nearer the support shaft than the other.
 10. A slay operatingmechanism as claimed in claim 1 in which each of the two cams has anactive surface consisting of two active faces one of which is locatednearer the respective support shaft than the other, corresponding activefaces on the two cams having the same profiles.
 11. A slay operatingmechanism as claimed in claim 9 in which the active face or faces ofeach cam are constituted by a closed groove in a disc mounted on therespective support shaft.
 12. A slay operating mechanism as claimed inclaim 9 in which the active face or faces of each cam are provided on ashoulder of a disc mounted on the respective support shaft, a spigot onone end of a connecting rod being provided to cooperate with saidshoulder, the other end of said connecting rod being pivoted to one endof the beam.
 13. A slay operating mechanism as claimed in claim 9 inwhich the active face or faces of each cam are provided on the profileof a disc mounted on the respective support shaft.
 14. A slay operatingmechanism as claimed in claim 13 in which each cam has a connecting rodwith a spigot at one end, the spigot being urged into contact with theprofile, the other end of the connecting rod being connected to one endof the beam.
 15. A slay operating mechanism as claimed in claim 9 inwhich each cam has at least two pairs of active faces, one of the pairsof active faces being nearer the respective support shaft than the otherpair, active faces of each of the pairs being alternately andequi-angularly spaced apart.
 16. A slay operating mechanism as claimedin claim 12 in which each connecting rod has, on the side opposite tothe spigot, a guide finger which is coaxial with the spigot, the guidefinger being engaged in a slide, the plane of which includes therespective support shaft.